Diario del proyecto Reptiles and Amphibians of California

It is one of only two species that broadly lives up to the “ring species” concept: the ensatina is considered to be a single species, but is characterized by a chain of interconnected populations around California’s Central Valley that can look strikingly different. While the intermediate populations can interbreed, the forms at the southern ends of the loop are so different that they can no longer mate successfully everywhere they meet.

https://news.mongabay.com/2019/03/super-variable-california-salamander-is-an-evolutionists-dream/

A federal judge has upheld critical habitat protection for Sierra Nevada yellow-legged frogs, the northern population of mountain yellow-legged frogs and Yosemite toads in California’s Sierra Nevada mountains. The ruling, issued late Wednesday, came from the U.S. District Court for the District of Columbia.

https://www.biologicaldiversity.org/news/press_releases/2019/california-frogs-03-28-2019.php

Bipedalism may have been favored in kangaroo rats to avoid ambush predators like vipers and owls, says UC Riverside biologist.

https://news.ucr.edu/articles/2019/03/27/high-speed-videos-capture-how-kangaroo-rat-escapes-rattlesnake-attack